Micro-acoustic resonator springy anchor based on offset acoustic reflector trenches

1 . An apparatus, comprising:

a first layer including a cavity; and

a second layer on the first layer and including:

an opening over the cavity;

an anchor on a side of the opening, the anchor being over the cavity and including a first segment and a second segment; and

a device in the opening and over the cavity and coupled to the anchor.

2 . The apparatus of claim 1 , wherein the first and second layers are part of an integrated circuit, the first layer includes a semiconductor material, and the second layer includes at least one of metal, a piezoelectric material, or the semiconductor material.

3 . The apparatus of claim 1 , wherein the anchor includes:

a third segment coupled to and angled from the first segment;

a first trench, a second trench, and a third trench, the first segment being between an edge of the anchor and the first trench, the second segment being between the first trench and the second trench, and the third segment being between the first trench and the third trench; and

wherein each of the first, second, and third trenches forms a respective acoustic reflective boundary.

4 . The apparatus of claim 3 , wherein the acoustic reflective boundary formed by the first trench has a different orientation from the acoustic reflective boundaries formed by the second and third trenches.

5 . The apparatus of claim 4 , wherein at least one of the first trench, the second trench, or the third trench is a concave trench relative to the device.

6 . The apparatus of claim 3 , wherein the anchor includes a fourth trench on a periphery of the first, second, and third trenches and extending along at least parts of the first, second, and third trenches.

7 . The apparatus of claim 3 , wherein the anchor is a first anchor, and the second layer further:

a second anchor over the cavity and opposing the first anchor, the second anchor coupled to the device and including:

a fourth segment, a fifth segment, and a sixth segment, the fourth segment coupled to and angled from the fifth and the sixth segments; and

a fourth trench, a fifth trench, and a sixth trench, the fourth segment being between an edge of the second anchor and the fourth trench, the fifth segment being between the fourth trench and the fifth trench, and the sixth segment being between the fourth trench and the sixth trench.

8 . The apparatus of claim 3 , wherein the device is a resonator, and dimensions of the first through third trenches are based on a target wavelength related to a resonant frequency of the resonator.

9 . An apparatus comprising:

a resonator portion over a cavity;

an anchor over the cavity, the anchor including trenches; and

a bridge over the cavity and coupled between the resonator and and edge of the anchor.

10 . The apparatus of claim 9 , wherein the trenches include a first trench extending from the edge and a second trench opposing the bridge.

11 . The apparatus of claim 10 , wherein:

the second trench has a first portion and a second portion;

the anchor includes a third trench and a fourth trench;

the first trench is on a first side of the second trench and extends from the edge and along the first portion;

the third trench is on a second side of the second trench and extends from the edge and along the second portion, and

the fourth trench is on a periphery of the first, second, and third trenches.

12 . The apparatus of claim 11 , wherein the second trench is a concave trench relative to the resonator.

13 . The apparatus of claim 11 , wherein each of the first, second, third, and fourth trenches is configurable as a respective acoustic reflector.

14 . The apparatus of claim 13 , wherein each of the first and third trenches is a concave trench relative to the resonator.

15 . The apparatus of claim 9 , wherein dimensions of the bridge and the trenches are based on a target wavelength related to a resonant frequency of the resonator.

16 . A method comprising:

forming a first layer including a cavity;

forming a second layer on the first layer;

forming a resonator in the second layer and over the cavity;

forming an anchor including trenches in the second layer and over the cavity, the anchor having an edge; and

forming a bridge over the cavity and between the resonator and the edge.

17 . The method of claim 16 , wherein forming the trenches includes:

forming a first trench, the first trench having a first portion and a second portion;

forming a second trench on a first side of the first trench, in which the second trench extends from an edge of the anchor and along the first portion;

forming a third trench on a second side of the first trench, in which the third trench extends from the edge of the anchor and along the second portion; and

forming a fourth trench on a periphery of the first, second, and third trenches, in which the fourth trench extends along at least parts of the first, second, and third trenches.

18 . The method of claim 17 , wherein each of the first, second, and third trenches forms a respective acoustic reflective boundary.

19 . The method of claim 18 , wherein at least one of the first, second, or third trenches is a concave trench.

20 . The method of claim 17 , wherein forming the anchor includes selecting dimensions of the bridge and the first through third trenches based on a target wavelength related to a resonant frequency of the resonator.

21 . The apparatus of claim 3 , wherein the second trench has a different curvature or extends along a different direction from a first portion of the first trench, and the third trench has a different curvature or extends along a different direction from a second portion of the first trench.

22 . The apparatus of claim 9 , wherein the cavity, the anchor, the bridge, and the trenches are part of an integrated circuit.

23 . The method of claim 16 , wherein the first and second layers are part of an integrated circuit.